Blood stains: the dossier

01 What it is made of

• Protein
• Minerals and metal

Blood contains protein. Heat can make protein-containing stains harder to remove. On washable materials, cool water is a common first step. A protein-digesting detergent is an option only when its label permits the actual fabric; use a suitable delicate-fabric detergent on wool or silk.

Blood contains iron bound within haemoglobin; it should not be treated as a simple rust stain. Start with the fabric-specific blood-stain advice rather than applying a general mineral or acid cleaner.

02 Field notes

• Blood contains proteins. Heat can make the stain harder to remove, so use cool water first when the fabric care label permits washing.
• Hydrogen peroxide fizzes on blood because catalase, an enzyme in blood, splits it into water and oxygen gas.
• Changes in haemoglobin contribute to the brown colour of old blood. A persistent stain does not automatically justify bleach or enzyme treatment on an incompatible material.

04 Every surface on file

05 Step by step: blood on sheets

The most-searched combination for blood. The full file adds the chemistry, the set-in variant and questions.

1. 1

   Flush with cold water

   Turn the item inside out and hold the stain under a cold running tap, so water pushes the stain back out the way it came in. Keep going until the water runs clear.

2. 2

   Enzyme pre-treat

   If the care label permits washing and the detergent is suitable for the fibre, pretreat or wash according to that product label. Do not extend the stated soak time or use ordinary enzyme detergent on wool or silk. Rinse as directed and air-dry before assessing the mark.

3. 3

   Peroxide for the shadow

   If a shadow remains, dab on 3% hydrogen peroxide, let it fizz for a few minutes, then rinse in cold water. Test on an inside seam first: it can lighten dyes.

4. 4

   Wash and check

   Wash as normal at the warmest temperature the care label allows (now that the protein has gone). Check the spot before it goes anywhere near a dryer; air-dry it if any trace remains, because heat sets what is left.

Open stain file № 3805

06 How the method changes by material

The order of steps stays the same everywhere; what changes is which products each material can take. Across the 26 files for blood:

• Hydrogen peroxide: left out on jeans, leather and suede. It bleaches indigo, so denim gets a light patch where the stain was.
• Enzyme ("bio") detergent: left out on silk and wool sweater. Protease enzymes digest protein, and silk is protein. Use an enzyme-free wool wash.
• Ordinary enzyme sprays: left out on wool rug. Protein-digesting enzymes can attack wool and silk; only use a product specifically labelled wool-safe.

07 The kit for blood

How often each product appears across the 26 files:

• Cold water
• Hydrogen peroxide 3%
• Enzyme laundry detergent
• Enzyme stain and odour cleaner
• Dish soap
• Wool wash (enzyme-free)
• Baking soda

08 Products worth keeping for blood

Hydrogen peroxide 3% 18 of 26 files

The 3% solution sold in brown bottles at pharmacies. A mild oxidising bleach. Use only a peroxide product labelled for the material, at its labelled strength and contact time; pretest and rinse as directed. Keep it in its dark bottle; use its expiry date and storage instructions. Fizzing on an arbitrary surface is not a reliable strength test.

Enzyme laundry detergent 10 of 26 files

Laundry detergent may contain protease, amylase, lipase or other enzymes; check the actual formulation and fabric restrictions. Pretreat or wash only as the detergent and care labels permit, using the stated dilution and contact time.

Enzyme stain and odour cleaner 6 of 26 files

A spray with enzymes and often live bacteria cultures that break down urine, vomit, faeces and other organic residue. Follow the exact material-specific product instructions. Avoid flooding foam, padding or wood; persistent or deep contamination needs professional assessment.

09 Why the surface matters

Blood is easy on quartz countertop and stubborn on wool sweater. On wool sweater, the usual tools are off the table: enzyme ("bio") detergent. Protease enzymes digest protein, and wool is protein. Use an enzyme-free wool wash.

Across the 26 surfaces on file, 21 rate easy or manageable, 5 stubborn and 0 tough or specialist. Delicate fibres (wool, silk, rayon), anything you cannot rinse (carpet, upholstery, mattresses) and porous stone push the rating up.

10 Also common: blood on couch

1. Sponge with cold water. Cold damp cloth: blot, repeat.
2. Spray an enzyme cleaner. Material-approved enzyme cleaner; follow label.
3. Dab with peroxide. Fabric-approved peroxide product only; follow label.
4. Rinse, blot, brush.

Open stain file № 3815

11 Prevention

Keep the item care instructions and a suitable fabric-labelled cleaner available. For washable items, prompt cool-water treatment may help; ordinary enzyme detergent is not suitable for every fabric.

12 Questions

13 Myth files

• Does saliva remove blood? Half true On a pinprick of fresh blood it helps about as much as a dab of cold water. Its main enzyme digests starch, not blood.
• Does meat tenderizer remove blood stains? Confirmed Yes, unseasoned tenderizer contains papain, a protein-digesting enzyme. Never on wool or silk.
• Does hydrogen peroxide remove blood? Confirmed Yes, especially on whites. It foams because blood's own catalase breaks it down. Test colours first.
• Does hot water set stains? Confirmed For protein stains, yes: heat cooks them onto fibres. For grease, warm water actually helps.